Paper Calendering Process
Servall Calendering solutions for all paper and board grades
Calenders are used in order to change the surface properties of uncoated paper or coated qualities or to manufacture paper with a certain density. The paper industry distinguishes between a series of calenders:
2-roller calenders, multi-roller calenders, super calenders for glazing, or highly heated multinip calender systems, which work both outside the paper machine calender (“offline”) and are also integrated in paper machines calender (“online”). Conversions in paper quality mean that calendering processes repeatedly have to be adjusted. Before costly new installations are necessary in these cases, the existing systems can be adapted with the
corresponding expertise and finely adjusted to the new tasks.
Calendering is the last step of the paper manufacturing process that impacts paper and board properties. Compression of the paper surface and its construction betters the surface properties, the most important of which are smoothness and gloss. Calenders are also used as pre-calenders before coating or size press. The main purpose of calendering is to improve the surface properties of paper and to control the caliper profile.
Servall can offer calendering solution for all paper and board grades. The type of calendering methodology applied is determined by calendar paper machine process conditions like speed and deckle as well as the paper or board quality. It is essential to choose the right concept for each application.
The Soft Nip Calender method utilizes rolls with a soft, elastic cover that kind a nip replicating the surface of the tempered roll with a hard surface – therefore rising the paper properties. The end normally enhances the performance characteristics and printability of the web.
Servall Hard Nip & Soft Nip Calender Advantages
- Provides high end product quality
- Ease of operation and maintenance
- Flexible combinations suitable to end product requirements
- With or without thermo rolls
- Fixed crown or crown control rolls
- Simple design and open frame
- Improved web feeding and runability